Interaction of age and specific saliva component output on caries

Implication of serum and salivary albumin tests in the recent oral health related epidemiological studies: A narrative review

Albumin is the most abundant protein in human serum and a specific amount of albumin also can be found in the saliva. It has several physiological functions such as blood colloidal osmotic pressure, antioxidant activity, binding and transporting of endogenous and exogenous substrates. We conducted an electronic search across several databases such as PubMed, Scopus, Cochrane, Embase and Science Direct using the relevant MeSH terms and keywords like "albumin", "serum albumin", "salivary albumin", "oral health" "dental caries" and "epidemiology". Only the epidemiological studies published between 2010 and 2023 were included. After the application of the inclusion criteria, a total of 51 studied were included in this narrative review. Serum and salivary albumin tests have been used in various aspects of oral health as a diagnostic and prognostic factor. Some of the results point out to a pattern of association while some of them are inconclusive and even contradictory. This narrative review discusses the role, significance and impact of albumin in epidemiological oral health related studies including the categories of periodontal health and disease, dental caries, oral function and hypofunction, nutrition and malnutrition, tooth loss and its treatment, diabetes and cancer. In addition, it offers a short manual for the researchers on when, where and how to use albumin tests in planning their study designs whether investigating an association or measure them as a covariate.

Salivary elemental signature of dental caries: a systematic review and meta-analysis of ionomics studies

Trace- and macro-chemical elements are crucial for cellular physiological functioning, and their alterations in biological fluids might be associated with an underlying pathological state. Hence, this study aimed to examine and summarize the published literature concerning the application of salivary ionomics for caries diagnosis. An extensive search of studies was conducted using PubMed, EMBASE, Web of Science, and Scopus, without any language and year restriction for answering the following PECO question: "In subjects (i.e., children, adolescents, or adults) with good systematic health, are there any variations in the salivary concentrations of trace- or macro-elements between caries-free (CF) individuals and caries-active (CA) subjects?" A modified version of the QUADOMICS tool was used to assess the quality of the included studies. The Review Manager Version 5.4.1. was used for data analyses. The analysis of salivary chemical elements that significantly differed between CF and CA subjects was also performed. Thirty-four studies were included, involving 2299 CA and 1669 CF subjects, having an age range from 3 to 64 years in over 16 countries. The meta-analysis revealed a statistically significant difference (p < 0.05) in the salivary levels of calcium, phosphorus, chloride, magnesium, potassium, sodium, and zinc between CA and CF subjects, suggesting higher levels of calcium, phosphorus, potassium, and sodium in CF subjects while higher levels of chloride, magnesium, and zinc in CA patients. Half of the included studies (17/34) were considered high quality, while the remaining half were considered medium quality. Only zinc and chloride ions were found to be higher significantly and consistent in CF and CA subjects, respectively. Conflicting outcomes were observed for all other salivary chemical elements including aluminum, bromine, calcium, copper, fluoride, iron, potassium, magnesium, manganese, sodium, ammonia, nitrite, nitrate, phosphorus, lead, selenium, and sulfate ions.

Role of Salivary Biomarkers in Diagnosis and Detection of Dental Caries: A Systematic Review

Saliva plays a significant role in oral health and tooth integrity. Salivary components reduce tooth surface exposure to demineralization, protect against teeth wear and aid in enamel remineralization. There is a growing attempt to use salivary markers in diagnosing or predicting caries. However, despite the current information, there has yet to be an agreement among scholars. This study seeks to contribute more evidence on the suitability of salivary biomarkers in dental caries diagnosis. Eligible studies were electronically searched on online databases PubMed, Elsevier's Scopus, EMBASE and Web of Science, and all the studies that met the inclusion criteria were considered. The PECOS criteria guided the study selection process based on the study question. The risk of bias was assessed using the STROBE checklist. Eighteen articles were included in the analysis. All the studies presented relevant data concerning the study objectives. There was evidence of associations between salivary biomarkers and dental caries, and the correlations were either positive or negative. The studies presented significant heterogeneity; thus, a meta-analysis was not possible. Salivary biomarkers appeared to perform crucial and complementary functions toward tooth integrity and thus may be reliable in predicting or diagnosing dental caries in patients.

The role of sugar-rich diet and salivary proteins in dental plaque formation and oral health

BACKGROUND

Dental plaque is a complex colorless film of bacteria that develops on the surfaces of teeth. Different mechanisms of microbial adhesion to tooth surfaces exist. Both non-specific and specific types of adherence have been anticipated.

HIGHLIGHT

The present review evaluated the effect of sugar-rich diet and salivary proteins on oral hygiene and dental plaque development.

CONCLUSION

The oral microbiota is essential for maintaining and reestablishing a healthy oral cavity. Different types of sugars have different effects on the inhibition and formation of dental plaque. The peptides, proteins, and amino acids secreted by parotid glands in the oral cavity facilitate neutralizing the acidity in dental plaque and preventing dental caries. A properly balanced diet is crucial for both a healthy oral cavity and the oral microbiome.

iTRAQ-based quantitative analysis of age-specific variations in salivary proteome of caries-susceptible individuals

Background

Human saliva is a protein-rich, easily accessible source of potential biomarkers for the diagnosis of oral and systemic diseases. However, little is known about the changes in salivary proteome associated with aging of patients with dental caries. Here, we applied isobaric tags for relative and absolute quantitation (iTRAQ) in combination with multiple reaction monitoring mass spectrometry (MRM-MS) to characterize the salivary proteome profiles of subjects of different ages, presenting with and without caries, with the aim of identifying age-related biomarkers for dental caries.

Methods

Unstimulated whole saliva samples were collected from 40 caries-free and caries-susceptible young adults and elderly individuals. Salivary proteins were extracted, reduced, alkylated, digested with trypsin and then analyzed using iTRAQ-coupled LC–MS/MS, followed by GO annotation, biological pathway analysis, hierarchical clustering analysis, and protein–protein interaction analysis. Candidate verification was then conducted using MRM-MS.

Results

Among 658 salivary proteins identified using tandem mass spectrometry, 435 proteins exhibited altered expression patterns in different age groups with and without caries. Of these proteins, 96 displayed age-specific changes among caries-susceptible adults and elderly individuals, and were mainly associated with salivary secretion pathway, while 110 age-specific proteins were identified among healthy individuals. It was found that the age factor caused significant variations and played an important role in both healthy and cariogenic salivary proteomes. Subsequently, a total of 136 target proteins with complex protein–protein interactions, including 14 age-specific proteins associated with caries, were further successfully validated using MRM analysis. Moreover, non-age-specific proteins (histatin-1 and BPI fold-containing family B member 1) were verified to be important candidate biomarkers for common dental caries.

Conclusions

Our proteomic analysis performed using the discovery-through-verification pipeline revealed distinct variations caused by age factor in both healthy and cariogenic salivary proteomes, highlighting the significance of age in the great potential of saliva for caries diagnosis and biomarker discovery.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1669-2) contains supplementary material, which is available to authorized users.

Salivary Protein Roles in Oral Health and as Predictors of Caries Risk

This work describes the current state of research on the potential relationship between protein content in human saliva and dental caries, which remains among the most common oral diseases and causes irreversible damage in the oral cavity. An understanding the whole saliva proteome in the oral cavity could serve as a prerequisite to obtaining insight into the etiology of tooth decay at early stages. To date, however, there is no comprehensive evidence showing that salivary proteins could serve as potential indicators for the early diagnosis of the risk factors causing dental caries. Therefore, proteomics indicates the promising direction of future investigations of such factors, including diagnosis and thus prevention in dental therapy.

Salivary proteins and microbiota as biomarkers for early childhood caries risk assessment

Early childhood caries (ECC) is a term used to describe dental caries in children aged 6 years or younger. Oral streptococci, such as Streptococcus mutans and Streptococcus sorbrinus, are considered to be the main etiological agents of tooth decay in children. Other bacteria, such as Prevotella spp. and Lactobacillus spp., and fungus, that is, Candida albicans, are related to the development and progression of ECC. Biomolecules in saliva, mainly proteins, affect the survival of oral microorganisms by multiple innate defensive mechanisms, thus modulating the oral microflora. Therefore, the protein composition of saliva can be a sensitive indicator for dental health. Resistance or susceptibility to caries may be significantly correlated with alterations in salivary protein components. Some oral microorganisms and saliva proteins may serve as useful biomarkers in predicting the risk and prognosis of caries. Current research has generated abundant information that contributes to a better understanding of the roles of microorganisms and salivary proteins in ECC occurrence and prevention. This review summarizes the microorganisms that cause caries and tooth-protective salivary proteins with their potential as functional biomarkers for ECC risk assessment. The identification of biomarkers for children at high risk of ECC is not only critical for early diagnosis but also important for preventing and treating the disease.

Visual scoring of non cavitated caries lesions and clinical trial efficiency, testing xylitol in caries-active adults

OBJECTIVES

To better understand the effectiveness of xylitol in caries prevention in adults and to attempt improved clinical trial efficiency.

METHODS

As part of the Xylitol for Adult Caries Trial (X-ACT), non cavitated and cavitated caries lesions were assessed in subjects who were experiencing the disease. The trial was a test of the effectiveness of 5 g/day of xylitol, consumed by dissolving in the mouth five 1 g lozenges spaced across each day, compared with a sucralose placebo. For this analysis, seeking trial efficiency, 538 subjects aged 21-80, with complete data for four dental examinations, were selected from the 691 randomized into the 3-year trial, conducted at three sites. Acceptable inter- and intra-examiner reliability before and during the trial was quantified using the kappa statistic.

RESULTS

The mean annualized noncavitated plus cavitated lesion transition scores in coronal and root surfaces, from sound to carious favoured xylitol over placebo, during the three cumulative periods of 12, 24, and 33 months, but these clinically and statistically nonsignificant differences declined in magnitude over time. Restricting the present assessment to those subjects with a higher baseline lifetime caries experience showed possible but inconsistent benefit.

CONCLUSIONS

There was no clear and clinically relevant preventive effect of xylitol on caries in adults with adequate fluoride exposure when non cavitated plus cavitated lesions were assessed. This conformed to the X-ACT trial result assessing cavitated lesions. Including non cavitated lesion assessment in this full-scale, placebo-controlled, multisite, randomized, double-blinded clinical trial in adults experiencing dental caries did not achieve added trial efficiency or demonstrate practical benefit of xylitol.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT00393055.

Co-relationships between glandular salivary flow rates and dental caries

OBJECTIVE

This study was designed to evaluate the relationship of age, gender, ethnicity and salivary flow rates on dental caries in an adult population using data collected from the Oral Health San Antonio Longitudinal Study of Aging (OH: SALSA).

BACKGROUND

Saliva is essential to maintain a healthy oral environment and diminished output can result in dental caries. Although gender and age play a role in the quantity of saliva, little is known about the interaction of age, gender and ethnicity on dental caries and salivary flow rates.

MATERIALS AND METHODS

Data from the 1147 participants in the OH: SALSA were analysed. The dependent variables were the number of teeth with untreated coronal caries, number of teeth with root caries and the number of coronal and root surfaces with untreated caries. The independent variables were stimulated and unstimulated glandular salivary flow rates along with the age, sex and ethnicity (e.g. European or Mexican ancestry) of the participants.

RESULTS

Coronal caries experience was greater in younger participants while root surface caries experience was greater in the older participants. Coronal caries was lower in the older age groups while the root caries experience increased. Men had a statistically significant (p < 0.02) higher experience of root caries than women. Values for unstimulated and stimulated parotid salivary flow rates showed no age difference and remained constant with age, whereas the age differences in the unstimulated and stimulated submandibular/sublingual salivary flow rates were significant. The mean number of teeth with coronal and root caries was higher in Mexican-Americans than in European-Americans.

CONCLUSIONS

Over one-fourth of the adults between the ages of 60 and 79 have untreated root caries over one-third having untreated coronal caries. Lower salivary flow rates play a significant role in both the number of teeth and the number of surfaces developing caries in these adults. Women and individuals of European-American ancestry experience less caries.

What is the true incidence of dental pathology in the total joint arthroplasty population?

One million total joint arthroplasties (TJAs) are performed annually in the United States. The incidence of oral disease has not been documented in this population. To understand the scope of disease, a descriptive longitudinal population-based study sought to define the true incidence of dental pathology in the TJA population. One hundred consecutive TJA patients from a dedicated arthroplasty practice were sent for dental clearance, including oral examination, cleaning, radiographs, and treatment of active decay. The incidence of pathology was documented. Of 10 patients, 23 (23%) were treated before being cleared for arthroplasty. Sixty-six procedures were performed--2.9 problems per patient. No patient developed TJA infection. Routine preoperative dental clearance revealed 23% incidence of pathology, and no patient developed TJA infection.

[Paradigm shift in conservative dentistry: from a mechanistic to a prevention-oriented perception]

The application of different preventive measures has resulted in a decline of clinically detectable carious lesions in children and adolescents. Not only have caries symptoms changed significantly, but the number of extracted teeth in adults has decreased. Due to these epidemiological facts, modern conservative dentistry is based on a careful risk analysis and caries diagnosis, which also takes into consideration biological and psychosocial components of caries etiology. Conservative dentistry will fail if the dentists are only interested in repairing defects. Simultaneous with the positive outcome of prevention, some unanswered problems have arisen, for which there are no adequate solutions. In young children, caries prevalence is still high and the restorative care of these primary teeth should be improved. For adolescents, early detection of carious lesions should be improved and polarization of caries prevalence should be eliminated. In older adults, evidence-based therapy options for treatment of erosions, abrasions, and root caries are lacking. For seniors needing general care, preventive and restorative concepts should be established.

Elderly at greater risk for root caries: a look at the multifactorial risks with emphasis on genetics susceptibility

Root caries is one of the most significant dental problems among older adults today. Many studies have demonstrated that older adults are at greater risk for developing root caries. Here we examine what risk factors older adults are prone to and explain how they contribute to higher rates of oral disease, in particular root caries. The elderly are at risk for root caries due to dentures, lack of dexterity, a shift from complex to simple sugars, and poor oral hygiene. Decreased salivary flow and its manifestations with other social/behavioral and medical factors may provide a more comprehensive explanation to a higher frequency of root caries in older adults.

Analysis of the salivary proteome in gingivitis patients

BACKGROUND AND OBJECTIVE

Gingivitis is a disease that is characterized by inflammation of the gingival tissue, which can progress to periodontitis and tooth loss. Although many studies have attempted to identify salivary proteins that are associated with the disease, this is the first study to use a proteomic approach to analyze and compare the proteomic profile of whole saliva from gingivitis patients and healthy controls.

MATERIAL AND METHOD

To analyze the saliva proteome, two-dimensional gel electrophoresis and liquid chromatography were used, followed by mass spectrometry.

RESULTS

The analyses showed that gingival inflammation was associated with increased amounts of blood proteins (serum albumin and hemoglobin), immunoglobulin peptides and keratins. In the control group, salivary cystatins, which were detected using capillary Liquid Chromatography on line to electrospray ionization Quadrupole Time-of-flight mass spectrometry, appeared to be more abundant.

CONCLUSION

This approach provides novel insight into profiles of the salivary proteome during gingival inflammation, which may contribute to improvements in diagnosis.

Study of human neutrophil peptides in saliva by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is used to rapidly characterize the human neutrophil peptides - HNP 1, 2, and 3 - in saliva. The saliva excreted from the parotid and sublingual/submandibular glands of 70 individuals were collected and examined using MALDI-TOF. The MALDI approach requires no sample pretreatment other than mixing the saliva-absorbing material with the matrix and drying under ambient conditions. Tissue paper was the best material for collecting the saliva samples because of its strong texture and high absorbance, and sinapinic acid was the best MALDI matrix for the analysis of the HNPs. HNPs were detected in almost all the samples collected from the parotid glands, with no obvious differences among age or gender. In contrast, the distribution of the HNPs in the samples collected from the sublingual/submandibular glands was age-dependent: no HNPs were detected for those collected from individuals younger than 30, but the HNPs were present in all of the samples collected from those older than 60 years. The increased probability of detecting saliva HNPs with age suggests that HNPs may function as a biomarker for aging.